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To Service Vacuum Breaker or Vacuum Regulator
1.
Remove cover cap
1
. Measure depth from top of cover to ferrule
5
for assembly.
2.
Hold Stem
2
from turning using screwdriver on end of stem.
3.
Unlock nut
3
from nut
4
and remove nut
3
.
4.
Slowly remove nut
4
maintaining pressure on spring ferrule
5
to prevent ejection of the spring from
the upper case.
CAUTION:
Do not allow stem
2
to unscrew during removal of nut
4
.
5.
Remove spring
9
.
6.
To service vacuum breaker, follow procedure for standard regulators by size.
7.
To service vacuum regulator, follow procedure for back pressure regulators by size.
Installation and Maintenance
Model 121 Regulators – Variations
Vacuums and Springs
Vacuum Range
w.c. vacuum
Spring
Size
(– w.c.)
Spring Color
Part Number
3" to 6-1/2"
Red-Black
143-82-021-00
3/4", 1" and 1-1/4"
5" to 8-1/2"
Blue-Black
143-82-021-01
121-8
8" to 14"
Green-Black
143-82-021-02
12" to 20"
Blue
143-16-021-04
18" to 30"
Green
143-16-021-05
1-1/2", 2" and 2-1/2"
3 to 6-1/2"
Red
143-16-021-03
121-12
5" to 8-1/2"
Blue
143-16-021-04
8" to 14"
Green
143-16-021-05
1
3
5
9
4
2
Vacuum Regulator
Vacuum Regulators
are used to maintain a certain negative pressure (vacuum) in enclosed spaces
such as tanks, vessels, chambers, piping systems, etc. In general, these are piped to the regulator
inlet and control line connections and the regulator outlet piped to the inlet of a vacuum pump
or other vacuum source.
Available pipe sizes are 3/4" thru 2-1/2", as listed on Page 24. Note on the cutaway drawing that
the spring assembly is arranged for an upward force on the valve. Also, the valve itself is normally
open and moves downward to close rather than upward as in the standard 121. With the exception
of certain parts involved in the foregoing, everything else is interchangeable with standard
121 regulators.
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